This invention relates to an optical film which is an image quality improved film and a liquid crystal display apparatus using the same.
Recently, image display apparatuses typified by a liquid crystal display panel are widely used as a display means in personal computers, work stations, etc. As to the quality of images displayed by using these apparatuses, high display contrast, wide angle of field properties, and the like are required.
In order to realize such image quality, JP-A 6-27454 discloses a liquid crystal display installing a micro lens array wherein a light shield film is formed at corresponding positions for each lens. JP-A 6-95099 discloses the use of a rear light source having high directivity as a light source for a liquid crystal display panel, and installation of a light diffusion plate between the liquid crystal display panel and the rear light source. Further, JP-A 10-39769 discloses as a screen in a rear projection type projection apparatus, a screen wherein alignment pattern of microlens of the screen and that of a light shield film are coincided.
As a process for producing a light shield layer used for improving the image quality mentioned above, that is a black matrix, there are generally known a process for forming a thin metal film, a process comprising coating a photosensitive resin dispersing a pigment such as carbon black, etc. or a photosensitive resin dissolving a dye such as a black dye, etc. on a substrate and exposing the coated film to light using photolithography, and the like.
But the prior art is insufficient for providing optical films having desired properties.
It is an object of the present invention to provide an optical film wherein a light shield layer excellent in light shielding properties is accurately placed in a desired position, and said optical film having wide angle of field properties, and an image display apparatus such as a liquid crystal display device installing such an optical film therein.
The present invention provides an optical film comprising an optical element capable of forming spatial distribution of light transmittance, and a light shield layer positioned on an opposite side of the optical element, said light shield layer being composed of a compound which changes light transmittance depending on irradiation of an energy beam, wherein the light transmittance passing the light shield layer is modulated spatially depending on a dose of energy beam.
The light shield layer can be modified variously for improving light shield properties and angle of field properties.
The present invention further provides an image display apparatus such as a liquid crystal display installing such an optical film.